Differences

This shows you the differences between two versions of the page.

--- sd-8516_assembly_language_part_ii [2026/02/14 02:50] – appledog
+++ sd-8516_assembly_language_part_ii [2026/02/21 15:31] (current) – appledog
@@ Line 209: / Line 209: @@
-== Lesson 19: Debugging Techniques
+== Lesson 11: Debugging Techniques
-There are several ways you can debug programs in SDA assembly. If you look at the console, inserting SED will turn on trace debugging and you will in general be able to see what the CPU is executing (if, debugging has been turned on during compilation). Otherwise you may need to HALT at any particular position and read the registers yourself. However if you can do neither, or are looking for something a bit more helpful, recall the methods of PRINTing that allow you to print messages.
+There are several ways you can debug programs in SDA assembly.
+=== SED/CLD
+In research or development builds, inserting SED will turn on trace debugging and you will be able to see what the CPU is executing. However, for release or community edition builds debugging has been turned off for speed. Therefore if you are interested in debugging your code and the console messages are not helping, you can use the following to help analyze and debug your code:
 === INT 05h IO_PUTNUM
-One way is to use IO_PUTNUM from int05 (CAM/IL interrupt):
+IO_PUTNUM is a CAM/IL function that prints a number (in b) to the screen:
     LDB #10                 ; print a number in b (0-65535)
     LDAH $63                ; IO_PUTNUM
     INT $05
 === INT 05h IO_PRINT_STR
+Similarly, IO_PRINT_STR will print a string followed by a newline.
         LDBLX @hello_world
         LDAH $66                ; IO_PRINT_STR
@@ Line 237: / Line 241: @@
 === INT 10h print string
-The interface for the above is based on the KERNAL BIOS interface in Int 10h.
+The interface for the above is based on the KERNAL BIOS interface from INT 10h.
         LDAH $26                ;   AH=26h: Write string at cursor
@@ Line 243: / Line 247: @@
         INT 0x10
-The underlying function that this calls is write_string, but outside of kernal assembly you will not have access to this function. This is because the labels are not shared outside of the compilation; you will however have direct access to this function via INT 10h.
+Note: The assembler will place a #13 (CR, hex $0D) inside the string if you type \n. However, if you are dealing with strings on your own you must handle this yourself. For this you can use the set cursor position call (INT 10h, AH=22h) or the CR and LF and scroll functions (1Ah, 1Bh and 1Ch, respectively).
-        LDBLX @hello_world
+You can also just call IO_NEWLINE from INT 05h, which calls **''@carriage_return''** and **''@linefeed''** internally.
-        CALL @write_string
-        CALL @carriage_return
-        CALL @linefeed
-For user use, the assembler will place a #13 (CR, hex $0D) inside the string if you type \n. Therefore although there is no carriage return function, you can do that via the set cursor position call (INT 10h, AH=22h) and you can send a CRLF pair by calling INT 10h, AH=26h on a string containing a newline (#13 or 0x0D).
-If you need to issue a newline on it's own you can store the cursor position, issue a CRLF at the bottom of the screen and then restore the cursor X position.
-Also, under the hood, IO_NEWLINE from int 05 calls **''@carriage_return''** and **''@linefeed''.**
 === INT 10h print char
@@ Line 278: / Line 273: @@
+== NEXT STEPS
+What's next is a world of adventure waiting for you to explore. Here are some resources to help you get started:
+* [[SD-8516 ISA Profile]] -- A detailed review of the opcodes available on the SD-8516.
+* [[VC-3 System Interrupt Table]] -- A comprehensive list of KERNAL routines.
+* [[wozmon]] -- A port of wozmon to the SD-8516, alongside instructions on how to use it to enter, load and save programs.
+* [[SD-8516 Assembly Language]] -- Now that you know the basics, you might want to try this!
+It's worth pointing out that most of this is intended to eventually be included or listed as part of the [[SD-8516 Programmer's Reference Guide]].